This invention relates to the high volume production of petri dishes filled with prepared culture media. The media is an agar based product that gels at 95.degree. F. approximately. A loose fitting cover completes the petri dish assembly. The filled dishes with cover on them are assembled in stacks of ten and bagged in heat sealed film.
The prior art practice of high volume producers has been to place the stacks in a horizontal infeed conveyor to the bagging machine. Each stack of ten dish assemblies is removed from a stacker by hand, held together by hand and then turned horizontal by hand and placed on the horizontal infeed conveyor with the dish assemblies on edge and the stack is held together between spring loaded lugs on the conveyor as the stack is carried on the conveyor to the bagger.
The stack of dishes is a loose unstable unit, and difficult to handle. I believe that the closest technology for handling this type of product shape is in the food industry, for things such as rice cakes, using the on-edge type of infeed. However, these types of products are basically stable and not critical of rough handling. The conventional methods for handling them are unsuitable for the needs of the prepared petri dish industry.
It is an object of my invention to provide that petri dishes with gelled medium in them be stacked and mechanically placed into a moving infeed drive system of uniformly pitched drive lugs whose direction of movement is 90.degree. to the axis of the stacks as they are produced.
It is another object that the integrity of the dish be maintained during the procedure.